Field of the Invention
The present invention relates to an analog timepiece and a control method of an analog timepiece.
Background Art
In the related art, an analog timepiece employs a stepping motor for operating an indicating hand such as an hour hand, a minute hand, and a second hand. The analog timepiece needs to reversely rotate the indicating hand in a fast-forward mode. In a case where the stepping motor can be reversely rotated in the fast-forward mode, it is necessary to decrease a holding torque of a rotor. However, in a case where the stepping motor is configured to have one coil, if the holding torque decreases, the stepping motor is likely to be out of step.
For example, as disclosed in Japanese Patent No. 4619081, the stepping motor which can be reversely rotated in the fast-forward mode includes a stepping motor including a stator having three magnetic pole portions and two coils (hereinafter, referred to as a “dual-coil motor”). In general, compared to the above-described stepping motor having one coil, the dual-coil motor is less likely to be out of step even if the holding torque decreases.
The dual-coil motor disclosed in Japanese Patent No. 4619081 has driving means for outputting a pulse for driving a rotor and thereafter outputting a pulse having a braking effect to prevent the rotor from being rotated one or more steps. This improves rotation reliability of the rotor.
Incidentally, according to the analog timepiece, in some cases, it is determined whether or not the rotor is rotated one unit step, based on an inductive voltage generated in the coil of the stator due to free vibration of the rotor, after the pulse for driving the rotor is output. In a case where it is determined that the rotor is not rotated one unit step, the pulse for driving the rotor is output again, thereby reliably rotating the rotor one unit step.